Apparatus for making metal castings.



s; LAKE, APPARATUS FOR MAKING METAL CASTINGS.

APPLICAT ON FILE'] AUG.9, IQIY. 1 %7%@@%Q Patentedl'fiuly 9, 1918.

2 SHEETS-SHEET1.

' b. LAKE. APPARATUS FOR MAKING METAL CASTINGS.

ARH ICATION FILED Aue 9.1917.

latented. July 9, 1918;

2 SHEETS-SHEET 2.

QSIMONILAKE, or MILFORD, coivivnc'rrcu'r.

' APPARATUS FOR MAKING METAL CASTINGS.

Specification of Letters Patent.

' Patented July 9, 1918.

Application filed August 9, 1917. Serial No. 185,277.

To all whom it may concern.-

Be it known" that I, SIMON LAKE, a citizen of the United States,residing at Milford, in the county of New Haven and State ofConnecticut, have invented certain new and useful Improvements inApparatus for Making Metal Castings, of which the following is aspecification.

The invention has for its object to provide an apparatus which willpermit themolten metal to flow freely into the mold without trappingair, thereby providing a solid or dense casting in which blow holes andsur face indentations or imperfections are positively avoided, henceminimizing the cost of machining and planing, and the consequent cost inthe production of the finished article, the construction and'operationbeing such that a partial vacuum is created within the mold 'to permitthe free flow of the molten metal as it is poured into the mold. Anotherobject of the invention is to provide means for stamping the metal so asto positively. exclude all air pockets, said stamping means also servingas a valve for controlling theadmission of the metal to the mold. An-

other object of the invention is to provide means for permitting theescape of excess quantities of air and gases which may accu mulate inthe mold either during the process of pouring the metal, or throughdampness of the molding sand.

The invention consists in constructing a mold of two sections, commonlyknown as the cope and drag, said sections being connected air-tight andmounted upon a base,

and covered by a top plate, the said top plate being also connectedair-tight to the cope and having a hopper mounted thereon into 40.

which the molten metal is, poured and allowed to set sufliciently topermit air bubbles to escape therefrom, said hopper having a plungervalve controlling the admission of the molten metal to the mold, andsaid plate also having an exhaust pipe connected thereto and adapted forconnection with a suction pump whereby to withdraw air from the mold soas to create a partial vacuum therein, and said plate also having a ventnormally closed by a diaphragm of considerably less strength than theframing of the cope and drag so as to permit the escape of air and gaswithout injury to the framing of the apparatus. -The invention furtherconsists in certain novel features of construction, combinations andarrangements of parts as will be hereinafter described and then claimed.

In the drawings, illustrating the invention, in the several figures ofwhich like parts are similarly designated, Figure l is a side elevationof my improved mold. Fig. 2 is a vertical transverse sectional View ofthe same, parts being broken away. Fig. 3 is a partial vertical sectionof a modified form of the lower section. 1

The mold proper is preferably constructed of two sections orflasks,'-viz., a lower section or flask 1, providing a frame for holdingthe drag 2, and an-upper section or flask 3 for holding the cope 4, thesections or flasks 1 and 3 being flanged at their upper and lower ends,as at 5, the abutting flanges of the said sections being securelyfastened together as by bolts and nuts 6, as shown. The abutting facesof the said flanges are provided with registering grooves 7. adapted forreceiving a suitable plastic quick hardening material, such as plasterof Paris, putty, or a mixture of litharge and sand, so as to provide aseal between the joint formed between the said flanges. Channels 8 areformed in the flanges 5 of the upper section and have their outer endsprovided with threaded sockets9 into which are screwed nipples of a pumpor pumps 10 by which the sealing material may be forced into the grooves7.

The lower end of the section or flask 1 is closed'preferably by a baseplate 11, whichis bolted to the lower flange 5 of the section or flask1, and the lower face of the said flange and the upper face of the saidbase plate 11 are provided with registering re cesses to provide annulargrooves or recesses 12 to which are connected pumps 13 for forcing asealing material into the said grooves 12 in a similar manner to thatdescribed with respect to the grooves 7 While I show the base plate as aseparate and detachable element of the lower section, it will, ofcourse, be understood that it i may be formed integral with said sectionas shown in Fig. 3, thus avoiding the necessity of providing a sealedjoint between the lower end'of the lower section and its base. As shownin Fig. 3, 1 is the lower section and 11 isits integral base. Thegrooves? and [12 are provided with vents 14 located, pref- The upper endof the section or flask 3 is closed by a plate 15, bolted to the upperflange 5 of the section or flask 3 and having its lower surface providedwith an annular 5 recess designed to register with .a similarly shapedrecess formed in the upper face of the upper flange 5, providing anannular recess 16 adapted to receive a suitable packing material to forman air-tight joint between the'plate or cover and the section or flask3.

As stated, the flask 1 is designed to receive the drag 2 of the mold,and the upper section or flask 3 is designed to .receive and 15 hold thecope 4, and it might be stated here,

that, in practice,.both the drag and the cope are constructed of anysuitable material,

passage or channel 19 leading into its base or lower end, and-with anoutlet 20 extending from the extreme upper end of the mold, .30 saidoutlet being in communication with an exhaust passage extending from avacuum pump (not shown), as will be hereinafter referred to, whereby asthe molten metal is poured into the mold, the metal will be permitted toflow freely into every crevice or compartment of the mold as will bebest.

understood from the subsequent general description of the operation ofthe apparatus. The top plate 15 'is formed with a boss 21 upon which issecurely bolted a casing 22 having a bore 23 registering with a bore 24formed in the plate 15. Bolted upon the upper flanged end of the casing22 is a hopper 25 into which the molten metal is' poured prior to itsdelivery to the mold. The walls of the hopper 25 are lined with asuitable refractory material 26, the said material being extended downinto the bore 23 and into the opening 24, and of substantiallycylindrical-form to provide a cylindrical passage 31 to receive thelower end of a plunger 27, which latter serves as, a valve to controlthe flow of the molten metal into the passageway 19 leading to the mold.

proper, The plunger is preferably constructed 'of a metallic core uponwhich is baked fire-clay, porcelain, or other suitable refractorymaterial 30, and the said metal core or rod is provided throughout itslength with a plurality of'concentrlc grooves or ribs 29 to provide alocking means'so as to prevent the displacement of the refractorymaterial 30. The lower end of the hopper 25 and the refractorylining 26,as

before stated, terminate in a cylindrical bore the hopper with thematerial to be fedthe mold, and which may also serve;

- furnace.

31, and the inner face of the cylindrical bore of the refractorymaterial 26, adjacent to the lower end of the cylindrical portionthereof, is provided with an annular recess 31, which communicates witha bore'or passage 32 formed in the lining 26 and having its outer end inopen communication with a bore 33 in a lug 33 integral with the casting22, said bore 33 having its outer end threaded to receive the shank of asuitable pump 34 whereby to force suitable packing materials into therecess 31 so as to provide a sealed joint between the periphery of theplunger 27 and the cylindrical portion of the lining 26. I 30 The plate15 is formed, preferably diametrically opposite the boss 21, with a boss39 having a transverse groove 40 in its upper face, which, with a plate4l bolted upon the upper surface thereof provides a chan- '85 nelway forthe reception of a ate-valve 42, the purpose of which will; e explainedhereinafter. Screwed into the plate 41 is an exhaust pipe 43, preferablylined with a refractory porous material, as shown at 44, in Fig. 2. Thepipe 43is extended from a suitable suction pump (not shown), and isprovided witha valve 45, whereby passage through the said pipe 43 may becontrolled.

'Arranged centrally of the plate 15 is a vent 46, the outer end ofwhichis closed by a diaphragm 47 of comparatively lightweight material,which is designed to. form a relief valve to permit the escape of excesspressures-of gases, air, or steam within the mold which might accrue inthe molding of the castings, and which ofttimes occur owing to dampnessin the molding sand, and in the formation of gases during the meltingand pouringv of the metal into the mold. The hopper 25 is formed with aspout 48, and with a channel 49 leading into the hopper 25, whereby thehopper may be drainedv of materials after the mold has been filled,

and, of course, before the metals have thoroughly cooled. The channel 49is held normally closed by a plug 5 0, as shown in Fig. 2.

Associated with the hopper 25 is a-ladle 51, shown in dotted lines inFig. 1 of the drawings, which may extend from or be. associated withsuitable smelting furnaces, and which serves as a conveyer to sup '1chute to guide the molten metal into mold as it is delivered .from thesmelting The advantages of my improved apparatus may be best understoodfrom the following description of the operation of the device After themold is baked, and while still warm, the pouring receptacle or hopper-25a d the vent pipe 43 are secured to the upper each time a casting ismade; it

plate 15 and the plate valve 42 is inserted in the slot 40 and sealed soas to provide an air-tight joint, the inner end of the slot beingpreferably closed tight by a suitable sealing material, such as putty,litharge and sand, or other suitable material so that the air Within themold mayv be withdrawn through the said pipe 43. Metal is now pouredinto the hopper, and when bubbling ceases the plunger 27 is elevatedsuificiently to permit the liquid metal to flow through the opening 19into the mold, enough metal being poured into the mold to allow it torise into the lower end of the vent tube a distance proportionate to thevacuum maintained and the specific gravity of the metal being poured. Assoon as the mold is filled the valve plate 42 is driven in through theslot, thus shutting oflf further rise of metal in the vent pipe 43. Theplunger 27 is then forced down upon the plastic metal to compress it inthe mold, hence making the metal more compact and homogeneous. I

When a number of castings are to be made from the same pattern, insteadof using all sand surrounding the pattern in the flasks, I purposemaking a semi-permanent mixture of cement or plaster, leaving only asmall quantity of sand to be dried in the oven being understood that nomoisture should be in the sand surrounding the casting, otherwise steammight be generated and burst the mold. However, in order to avoid injuryto the mold in such an event, I provide the vent 46, which. is coveredby the plate 47, as previously described. It will be seen that the plate47 then acts as a safety valve, and is of such strength only as topermit of its being blown out or broken before there is enough pressureto burst the flask or blow off the coverof the mold or otherwise injurethe mold.

It will thus be seen that my invention provides, first, for pouring themetal so that no air will be trapped in the mold during the process ofpouring; second, for taking off all gases from the mold as rapidly asformed by forming a vacuum in the mold; third, for creating theequivalent of a high gate to the mold by atmospheric pressure whilepouring; fourth, for so preparing the mold that it will withstand highpressures.

without distortion, and fifth, for applying a high compression to themetal in the mold while still in a liquid or plastic state.

What I claim is i 1. In combination, a flask and its base adapted toform the drag, and a flask and its top plate adapted to form the cope,the meeting edges of the flasks being hermetiafter it enters the molcally sealed, a mold arranged in the flasks and having a feeding passageor channel leading thereto at or near one end and an exhaust passageleading therefrom at or near the opposite end, and means to control theintroduction of molten metal to the feeding passage and apply pressurethereto after it enters the mold.

2. In combination, a flask and its base adapted to form the drag, and. aflask and its top plate adapted to form the cope, the meeting edges ofthe flasks being hermetically sealed, a mold arranged in the flasks andhaving a feeding passage or channel leading to its bottom and an exhaustpassage leading therefrom at or near its top, a hopper erected on theplate of the cope and terminating in a cylindrical portion opening intothe feeding passage, and a plunger arranged in said hopper and adaptedto control the flow of metal from the hopper through the cylindricalportion to the feeding passage and then to be moved toward the feedingpassage to apply pressure to the metal fed from the hopper into thefeeding passage.

flask and its base its top plate adapted to form the cope, the

meetlng edges of the flasks being hermetlcally sealed, a mold arrangedin the flasks and having a feeding passage or channel leading thereto ator near one end and an exhaust passage leading therefrom at or near theopposite end, and means to control the introduction of molten metal tothe feeding passage and ap ly pressure thereto the exhaust passage beingintercepted transversely by a sliding valve.

4. In combination, a flask and its base adapted to form the drag, and aflask and its top plateadapted to form the cope, the meeting edges ofthe flasks being hermetically sealed, a mold arranged in the flasks andhaving a feeding passage or channel leading thereto at or near one endand an exhaust passage leading, therefrom at or near the opposite end,and means to control the introduction of molten metal'to the feedingpassage and apply pressure thereto after it enters the mold, the exhaustpassage being intercepted transversely by a sliding valve, and afrangible relief valve located in the cope plate.

In testimony whereof I have hereunto set my hand this 2 day of August,A. D. 1917.

SIMON LAKE. Witnesses:

O. E. ADAMS,

M. D. BLONDEL.

to form the drag, and a flask and

